Stretcher frame for oil paintings



March 8, 1966 B. MUNN STRETCHER FRAME FOR OIL PAINTINGS 2 Sheets-Sheet l Filed Jan. 9, 1964 Qa, i {',5

INVENTOR. N M U NN BY :f

March 8, 1966 B. MUNN STRETCHER FRAME FOR OIL PAINTINGS Filed Jan. 9, 1964 2 Sheets-Sheet 2 INVENTOR. BEN M UNN www United States Patent O 3,238,996 STRETCHER FRAME FOR OIL PAINTINGS Ben Munn, 87-41 Santiago St., Hollis, N.Y. Filed Jan. 9, 1964, Ser. No. 336,753 1 Claim. (Cl. 1mi-374.1)

This invention relates to a frame assembly for use in connection with an artists canvas and more particularly concerns a frame assembly for stretching and holding in a taut condition a canvas secured thereto.

One object of the invention is to provide an improved rectangular frame assembly of simplified construction having frame bars which are independently adjustable at each of the corners of the frame assembly for stretching and holding a canvas in a wrinkle-free condition.

A further object is to provide a frame assembly as described wherein the adjustment means for the bars includes right-angle bolts having ends slidably disposed in holes in the bars at each corner of the frame assembly, with a cam disk movably disposed in slots in the adjacent ends of each pair of bars at each corner of the frame assembly to retain uniform tension throughout the canvas.

For further comprehension of the invention, and of the objects and advantages thereof, reference will be had to the following description and accompanying drawings, and to the appended claim in which the various novel features of the invention are more particularly set forth.

In the accompanying drawings forming a material part of this disclosure:

FIG. 1 is a perspective view of a frame assembly embodying the invention, with a canvas mounted thereon, a part of the canvas at one corner of the frame assembly being broken away.

FIG. 2 is an enlarged rear view of the frame assembly with the canvas mounted thereon.

FIG. 3 and FIG. `4 are cross-sectional views taken on lines 3-3 and 4 4, respectively, of FIG. 2.

FIG. 5 is a fragmentary sectional view taken on line 5-5 of FIG. 4.

FIG. 6 is an exploded perspective view of parts of the frame assembly.

Referring to FIGS. l-6 of the drawing, there is shown a frame assembly 10 upon the front or forward side of which is stretched a sheet of canvas 12. The frame assembly includes two parallel end bars 15, 16 and two side bars 17, 18 arranged to define a rectangular frame. Each bar in cross section, as best shown in FIGS. 3 :and 4, has a trapezoidal cross section. The wide rear side or wall 19 of each bar is perpendicular to the narrower outer wall 20 and inner wall 21, Inner wall 21 is parallel to and narrower than outer wall 20. Front wall 22 is disposed at an obtuse angle to inner wall 21 and at an acute angle to outer wall 20. Thus the stretched canvas sheet contacts each of the frame bars only at the common forward edge 23 where front wall 22 joins outer wall 2%, and extends -over but out of contact with the front walls 22 of all the bars. The edges 24 of the canvas are secured by tacks 25 to the outer walls 26 of the bars all around the frame.

Each bar has oppositely inclined end faces 26, each of which is trapezoidal in shape with wide front and back edges 22', 19 and narrow inner and outer edges 2i', 20. Edge 21 is shorter than edge 20. The end faces 26 extend oppositely at angles of to the inner wall 21 and outer wall 20 of each bar. An Unthreaded, smooth bore or hole 32 with a blind outer end is formed in each end of each bar. The hole extends outwardly from inner wall 21 perpendicular to outer wall 20 and parallel to rear wall 19. A flat, narrow slot or groove 33 is formed in each end of each bar. This slot has a circularly curved inner side 34 and flat, parallel opposing walls 37, 38. Each slot extends from inner end corner or edge 21 to a point 3,238,996 Patented Mar. 8, i966 ICC near outer end corner or edge 20 lof each end of each bar. Opposing slots 33 in adjacent ends of the bars at each corner of the frame dene an elongated at pocket. The at opposing sides 37, 33 of each slot 33 are aligned with the corresponding ilat opposing sides of the adjacent slot. The adjacent corner slots of the frame receive circular disks 40 which serve as cam members in the slots between walls 37, 38 and the opposing curved sides 34.

Right-angle bolts 42 are provided at the four corners of the frame. Each 'bolt 42 has two threaded arms 44. Nuts 46 are threaded on the arms. The arms 44 have their free ends axially and slidably disposed in the holes 32 at adjacent ends of each pair of arms of the frame.

The canvas is shown in FIG. l in a perfectly smooth, unwrinkled and stretched taut condition at the front of the frame assembly. When the canvas was first tacked to the frame wrinkles W indicated by dotted lines in FIGS. l and 2 extended irregularly across the canvas. To remove these wrinkles, nuts 46 and 46" at the upper corners of the frame as viewed in FIGS. l and 2 were tightened or adjusted on the arms 44 of the bolts 42 thereat to move the arms axially in holes 32 at the opposite ends of upper bar 15. This caused the bar 15 to separate from the upper ends of bars 17, 1S. The upper disks 40', 40" are cammed in the slots at the upper corners of the frame, and as shown in FIG. 2 are stabilized by contact between curved sides 34 `of the slots 33 at the ends of bar 15, and the opposing curved sides of the slots at the upper ends of bars 17, 18. Thus a rigid joint is formed at each corner of the frame with tension applied uniformly across the canvas between the upper and lower bars 15, 16 and between side bars 17, 18. If wrinkles W should extend longitudinally of the canvas they can be eliminated by adjusting any one or more of the nuts at the side bars 17, 1S. After all wrinkles have been eliminated, further tightening of the nuts on the arms 44 of all the bolts 42 will tension the canvas in all directions to form a uniformly taut, iiat surface supported only at its edges, which is most desirable for painting purposes.

It will be noted that a 'particularly characteristic feature of the invention is the independent adjustment provided for each end of each bar. Two adjustments are provided at each corner of ,the frame, or eight adjustments in all. The cam disks cooperate with the nut and bolt adjustments in that they automatically are cammed into positions where the Icorner structure is stabilized at each corner of the frame as the nuts thereat are tightened against inner sides 21 of the frame bars.

The invention may be applied to frames of different sizes, to bars of different thicknesses, and to canvas of different sizes and weights. The fr-ame bars are preferably made of wood but they may be made of plastic, metal or other materials. The frame bars can be shaped inexpensively on mass production woodworking or metal workin-g machinery, or they can be extruded inexpensively in plastic molding machinery lat high speed and low cost. The frames are easy to assemble and use. They can be supplied commercially in kits which can be stored compactly in small packages for assembly into frames when desired.

\Vhile I have illustrated and described the preferred embodiment of my invention, it is to be understood that I do not limit myself to the lprecise construction herein disclosed and .that various changes and modifications may be made within the scope of the invention as defined in the appended claim.

Having thus described my invention, what I claim as new, and desire to secure by United States Letters Patent A frame assembly for -stretching and holding a painting canvas, comprising a plurality of straight bars disposed .in a rectangular array with each end of each bar disposed adjacent to an end of another bar to define a frame corner, each bar having inner and outer opposing parallel walls, a rear wall Iperpendicular to the inner and `outer walls, and a front wall disposed at an acute angle .to the outer wall to dene a forward outer edge and disposed at an obtuse angle 1t0 the inner Wall to define a recessed inner edge located in a plane rearwardly of the forward edge, whereby a canvas sheet stretched over the front walls of the bars will contact only the forward outer edges, each bar having an elongated semielliptical narrow slot formed in each end thereof, each slot having a curved inner side terminating at opposite ends at an end face of the bar, a circular cam disk adjustably disposed in each pair of opposing slots at each frame corner, each bar having a hole near each end thereof extending outwardly from the inner wall toward and axially perpendicular to the inner and outer walls, a plurality of right-angle bolts having mutually perpendicular threaded arrns slidably engaged respectively in the holes at adjacent ends of two bars at each frame corner, and nuts threaded on the respective arms and engaging the inner walls of said bars for adjustably sliding the arms in the -holes to adjust the spacing of the adjacent bars with respect to each other, the disks being adjustably cammed in opposing slots at the frame corners while the nuts thereat are adjusted on the arms of the bolts, whereby wrinkles in said canvas are eliminated and said canvas is stretched and held taut on the bars.

References Cited by the Examiner UNITED STATES PATENTS 371,934 10/1887 Gray 1GO-374.1 472,021 4/1892 Anderson 160-371 1,128,362 2/1915 Rawbon Mtl-374.1 1,876,486 9/1932 Britten 16C-374 1,916,023 6/1933 Shull l60-374.l 2,247,235 6/1941 Hause 4-170 HARRISON R. MOSELEY, Primary Examiner.

20 FRANK B. SHERRY, Examiner.

C. A. NUNBERG, P. C. KANNAN, Assistant Examiners. 

